A major US study has released findings that point to an increased risk of schizophrenia in adolescents who inherit particular genes.

Whilst the disease is already known to have a particular genetic component, the new research links the disease with specific gene variants. A link was also made between the disorder and a biological process called synaptic pruning – which is the degradation or elimination of connections between brain cells.

The study, published in the online journal, Nature, by researches from the Broad Institute of MIT and Harvard, hope that the breakthrough will address the root causes, instead of just focussing on psychosis.

Eric Lander, director of the Broad Institute, said: “For the first time, the origin of schizophrenia is no longer a complete black box. While it’s still early days, we’ve seen the power of understanding the biological mechanism of disease in other settings. Early discoveries about the biological mechanisms of cancer have led to many new treatments and hundreds of additional drug candidates in development. Understanding schizophrenia will similarly accelerate progress against this devastating disease that strikes young people.”

The researchers analysed DNA samples from 100,000 people across 30 different countries. Through these samples, researchers were able to identify a particular gene, called complement component 4 (C4), a part of the immune system.

Genetic analysis conducted between 65,000 people found that those who had a particular form and expression of the C4 gene, were more likely to develop schizophrenia.

Additional research found that C4 played a significant role in pruning synapses during maturation of the brain, especially during adolescence. The higher the C4 activity, the more elimination occurred between brain cells during development.

The symptoms of schizophrenia tend to show their first signs in late adolescence, which may correlate with the C4 gene and its role in pruning synapses.